Coupling for mill rolls

ABSTRACT

A coupling for a mill roll and the like comprises a connector having a coupling bore therein, with the bore having a first surface shaped for close fitting engagement with a neck portion of the roll adjacent one extremity of the coupling engagement therebetween and a second surface shaped for close fitting engagement with the roll neck adjacent the opposite extremity of such engagement and a third surface disposed generally between the first and said second surfaces shaped for an increasingly close fit with the roll neck as the roll neck is increasingly inserted into the connector.

United States Patent [191 Petros et a1.

[ 1 COUPLING FOR MILL ROLLS [75] Inventors: Andrew .1. Petros, Oakdale; Clement S. Rybar, Pittsburgh, both of Pa.

[73] Assignee: Mesta Machine Company,

Pittsburgh, Pa.

[22] Filed: May 8, 1972 [21] Appl. No.: 251,300

[52] US. Cl 64/5, 64/8, 64/6,

[111 3,779,037 51 Dec. 18, 1973 Kater Primary Examiner-Manuel A. Antonakas Assistant ExaminerRanda1l Heald Attorney-Donn .1. Smith 5 7 ABSTRACT A coupling for a mill roll and the like comprises a connector having a coupling bore therein, with the bore having a first surface shaped for close fitting engagement with a neck portion of the roll adjacent one extremity of the coupling engagement therebetween and a second surface shaped for close fitting engagement with the roll neck adjacent the opposite extremity of such engagement and a third surface disposed generally between the first and said second surfaces shaped for an increasingly close fit with the roll neck as the roll neck is increasingly inserted into the connector.

14 Claims, 3 Drawing Figures 1 COUPLING FOR MILL ROLLS The present invention relates to a coupling for mill rolls, and more particularly to a coupling of a character described which is structured to facilitate a quick and reliable coupling of the components thereof for roll changing purposes.

In a rolling mill the work rolls of each mill stand are usually connected through spindle couplings, allowing a limited extent of universal motion, to the drive mechanisms for the roll. With frequent changing of the work rolls throughout the course of operation of the mill it is essential that the work rolls can be quickly removed from the spindle couplings and that the replacement rolls can be quickly and reliably connected thereto. In the case of finishing work rolls, the roll changing operation usually takes place every two to six hours of opera tion owing to rapid wearing of rolls. Previous coupling configurations have not permitted a quick and reliable roll changing operation consistent with maximum production and a minimum of mill down time.

The present invention provides means for quickly and reliably aligning the several components of a mill roll coupling arrangement such that a close fit at the ends of the engagement between the coupling and the roll neck are obtained. This results in positive mating of the coupling components. On the other hand, tapering surface configurations together with adequate champfering ensure that liberal clearances are available for insertion of the roll neck into the coupling. Close engagement. is accomplished near the end of the entering operation, as increasingly close clearances guide the roll neck into a quick and reliable coupling. Conversely, close clearances are provided at parallel roll neck flats for imparting maximum torque to the work roll.

I accomplish these desirable results by providing a coupling for a mill roll and the like, said coupling comprising a connector having. a coupling bore therein, said bore having a first surface shaped for close fitting engagement with a neck portion of said roll adjacent one extremity of the coupling engagement therebetween and a second surface shaped for close fitting engagement with said roll neck adjacent the opposite extremity of said engagement and a third surface disposed generally between said first and said second surfaces shaped for an increasingly close fit with said roll neck as said roll neck is increasingly inserted into said connector.

I also desirably provide a similar coupling wherein said second surface is formed on a projection sup ported in said connector and insertable into a complementary shaped recess in. said roll neck.

I also desirably provide a similar coupling including a roll neck portion shaped for insertion into said coupling bore, said portion including. constant tolerance surfaces for close fitting engagement with said first andsaid second connector surfaces and avarying tolerance portion shaped for increasingly close engagement with said third connector surface.

I also desirably provide a similar coupling wherein driving; flats are separated by diametric portions of said third surface, said third surface portions having a conical. configuration.

During. the foregoing discussion, various objects, features and: advantages of the invention have been set forth. These and other objects, featuresand advantages of the invention together with structural details thereof will be elaborated upon during the forthcoming description of certain presently preferred embodiments of the invention and presently preferred methods of practicing the same. i

In the accompanying drawings I have shown certain presently preferred embodiments of the invention and have illustrated certain presently preferred methods of practicing the same wherein:

FIG. 1 is a longitudinally sectioned view of one form of mill roll coupling arranged in accordance with the invention;

FIG. 2 is a cross-sectional view of the coupling as shown in FIG. 1 and taken along reference line IIll thereof; and

FIG. 3 is another cross-sectional view of the coupling as shown in FIG. 1 and taken along reference line III- III thereof. r

Referring now more particularly to the drawings the exemplary form of the mill roll coupling 10 shown therein comprises a connector 12 having a coupling bore 14 therein. The coupling bore 14 is arranged for an initial, relatively loose fitting engagement and then a close-tolerance engagement with roll neck 16. In furtherance of this purpose the roll neck 16 includes a coupling end portion 18 constructed in accordance with the invention for a surprisingly quick-attack but reliable engagement with the connector 12. The roll neck end portion 18 comprises a pair of driving or torque transmitting flats 20, 22 FIG. 3), which, when inserted into the connector 12 closely engage a complementary pair of driving flats 24, 26 of the connector 12. Desirably the torque transmitting flats 20-26 of the roll neck and connector are substantially parallel and are formed with close-fitting tolerances.

To facilitate a quick initial engagement between the roll neck end portion 18 and the connector 12 these components are provided respectively with champfered edges 28, 30. In the illustrated arrangement of the mill roll coupling 10, the major proportions of the arcuate surfaces extending between the roll neck flats 20, 22 are tapered or made slightly conical at reference characters 32, 34. The corresponding arcuate surfaces of the connector 12 similarly are tapered or conical, and in this example such taper is imparted to connector surfaces 36, 38 of the connector 12. Depending upon the application of the invention the connector 12 can be fabricated from a high-grade steel for maximum torque carrying capability. The connector 12 can be provided with replaceable liners (not shown) at its driving flats 24, 26 for engagement with the roll neck flats 20, 22. The remainder of the arcuate surfaces of the coupling end portion 18 of the roll neck 16 desirably are cylindrical at reference characters 40, 42. The'corresponding surfaces of the connector 12 likewise are of complementary cylindrical configuration.

The purpose of the conical surfaces 32-38 is the provision of relatively looseor liberal clearances between the coupling end portion 18 of the roll neck and the connector 12 when the roll neck initially is inserted into the coupling bore 14. As the coupling components are moved together to the final inserted position of the roll neck 16, the tolerances become "tighter until a close coupling fit is attained when the cylindrical portions 40; 42 of the roll neck are inserted into the complementarily shaped portion of the connector 12. This can provide a very close fit adjacent one end of the engagement between the roll neck 16 and the connector 12 without, however, interferring with the initial entry of the roll neck end portion 18 into the connector 12. Thus, a quick-attach but reliable engagement between the connector 12 and the roll neck 16 is attained. The use of constant, close-fitting tolerances at the driving flats 2026 has been found unexpectedly to not interfer with initial, quick insertion of the roll neck 16 into the connector 12, assuming proper alignment of the roll.

In further accordance with the invention a second close fit is surprisingly provided by the coupling arrangement adjacent the other end of the engagement between the roll neck 16 and the connector 12. In furtherance of this purpose a supporting disc 44 or other suitably shaped member is secured in the connector 12 (as by welding or shrink-fitting) adjacent the inward extremity of its coupling bore 14. A sturdily constructed projection 46, formed for example integrally with the support disc 44, protrudes toward the roll neck 16, when the latter is engaged with the connector 12. The projection 46 includes an annular extension 50 which is closely seated in annular recess 52 milled in the adjacent end surface of the roll neck 16 when the roll neck is fully engaged within the connector 12, as best shown in FIG. 1. Desirably an operating clearance 54 remains at the bottom of the annular recess 52. When thus inserted the projection 46 and its engagement with the adjacent end of the roll neck end portion 18 provides a second close-tolerance fit, which is most appropriately located adjacent the other extremity of the engagement between the connector 12 and roll neck end portion 18. This close engagement is accomplished near the end portion of the entering operation, as the tapered pilot clearances at the conical or tapered surfaces 32-38 guide the roll neck end portion 18 and the connector 12 into a close-tolerance coupling fit.

In the operation of the coupling 10, the roll neck end portion 18 can be quickly removed from the connector 12 simply by withdrawing these components longitudinally. A replacement roll can be quickly engaged with the coupling 10 simply by initial engagement of the champfered portions 28, 30 followed by an increasingly close tolerance entry movement as the neck end portion 18 of the replacement roll is inserted into the connector 12. As the junctions 56 between the respective roll neck surfaces 32, 40 and 34, 42 engage the corresponding outer ends of the cylindrical connector surfaces 58 a first close tolerance fit is established adjacent the outer end of the coupling bore 14. Further entry movement of the roll neck 16 and/or connector 12 brings the projection 46 and the annular recess 52 of the roll neck 16 into close fitting engagement to establish a second close-tolerance fit at the other end of the coupling engagement between the connector 12 and roll neck end portion 18. At the end of entry movement, a third close-tolerance fit between the tapered roll neck surfaces 32, 34 and the tapered coupling surfaces 36, 38 is attained. As evident from the drawings, these surfaces are shaped to prevent angular displacement of the, roll neck 16 relative to the coupling, when the roll neck is fully inserted. It is further evident that the first and second surfaces provide an initally and continously closed-fitting engagement throughout the inserting movement of the roll neck 16 into the connector 12, for substantially the same purpose.

When thus assembled, torque is transmitted to the connector 12 and thence to the substantially parallel driving flats 20, 22 of the roll neck 16, which are closely and respectively engaged with parallel driving flats 24, 26 of the connector 12. Torque is transmitted in turn to the connector 12 by spindle 58, connected to a suitable driving mechanism (not shown). The spindle 58 terminates in a more or less conventional universal joint component or gear tooth coupling 60, which is keyed to the connector 12 as denoted by reference characters 62.

A thrust plate 64 of the spindle 58 engages through thrust button 66 the adjacent surface of the connector support disc 44 of the coupling 10 for purposes of thrust absorption.

From the foregoing it will be seen that a novel and efficient coupling for mill rolls has been described herein. The descriptive and illustrative materials employed herein are utilized for purposes of exemplifying the invention and not in limitation thereof. Accordingly, numerous modifications of the invention will occur to those skilled in the art without departing from the spirit and scope of the invention. Moreover, it is to be understood that certain features of the invention can be used to advantage without a corresponding use of other features thereof.

We claim:

1. A coupling for a mill roll and the like, said coupling comprising a connector having a coupling bore therein, said bore having a first surface shaped for close fitting engagement with a neck portion of said roll adjacent one longitudinal extremity of a coupling engagement therebetween, a second surface shaped for close fitting engagement with said roll neck adjacent the opposite extremity of said coupling engagement, and a third surface disposed generally between said first and said second surfaces and shaped for an increasingly close fit with said roll neck as said roll neck is increasingly inserted into said connector.

2. The combination according to claim 1 wherein said second surface is formed on a projection supported in said connector and insertable into a complementary shaped recess in said roll neck.

3. The combination according to claim 2 wherein said first surface and said third surface include cylindrical and conical surfaces respectively.

4. The combination according to claim 2 wherein said projection is mounted on a support disc mounted within said connector adjacent the inward extremity of said coupling bore.

5. The combination according to claim 1 wherein fourth surfaces including a pair of substantially parallel driving flats are formed in said coupling bore for engagement with complementary driving flats on said roll neck.

6. The combination according to claim 1 including a roll neck portion shaped for insertion into said coupling bore, said portion including constant tolerance surfaces for close fitting engagement with said first and said second connector surfaces and avarying tolerance portion shaped for increasingly close engagement with said third connector surface.

7. The combination according to claim 6 wherein said first connector surface and said roll neck constant tolerance portion are cylindrical, and said connector third surface and said roll neck varying tolerance portion are arcuate and tapered.

8. The combination according to claim 7 wherein said cylindrical and said tapered surfaces each include tions of said third surface, said third surface portions each having a conical configuration.

12. The combination according to claim 1 wherein each of said first, said second and said third surfaces is disposed to prevent angular displacement of said roll neck relative to said coupling bore when said roll neck is fully inserted into said connector.

13. The combination according to claim 1 wherein each of said first and said second surfaces are shaped for initially and continuously close-fitting engagement with complementary surfaces respectively of said roll neck as said roll neck is progressively inserted into said coupling bore.

14. The combination according to claim 1 wherein each of said first and said second surfaces is shaped to prevent angular displacement of said roll neck relative to said coupling as said roll neckis progressively inserted into said coupling bore. 

1. A coupling for a mill roll and the like, said coupling comprising a connector having a coupling bore therein, said bore having a first surface shaped for close fitting engagement with a neck portion of said roll adjacent one longitudinal extremity of a coupling engagement therebetween, a second surface shaped for close fitting engagement with said roll neck adjacent the opposite extremity of said coupling engagement, and a third surface disposed generally between said first and said second surfaces and shaped for an increasingly close fit with said roll neck as said roll neck is increasingly inserted into said connector.
 2. The combination according to claim 1 wherein said second surface is formed on a projection supported in said connector and insertable into a complementary shaped recess in said roll neck.
 3. The combination according to claim 2 wherein said first surface and said third surface include cylindrical and conical surfaces respectively.
 4. The combination according to claim 2 wherein said projection is mounted on a support disc mounted within said connector adjacent the inward extremity of said coupling bore.
 5. The combination according to claim 1 wherein fourth surfaces including a pair of substantially parallel driving flats are formed in said coupling bore for engagement with complementary driving flats on said roll neck.
 6. The combination according to claim 1 including a roll neck portion shaped for insertion into said coupling bore, said portion including constant tolerance surfaces for close fitting engagement with said first and said second connector surfaces and a varying tolerance portion shaped for increasingly close engagement with said third connector surface.
 7. The combination according to claim 6 wherein said first connector surface and said roll neck constant tolerance portion are cylindrical, and said connector third surface and said roll neck varying tolerance portion are arcuate and tapered.
 8. The combination according to claim 7 wherein said cylindrical and said tapered surfaces each include a pair of diametrically opposed surface portions separated by a pair of essentially parallel torque-transmitting flats.
 9. The combination according to claim 5 wherein the roll neck flats are closely fitted with the connector flats throughout entry and engagement therebetween.
 10. The combination according to claim 2 wherein said projection includes an annular extension seatable within a closely fitting annular recess formed in an adjacent end surface of said roll neck.
 11. The combination according to claim 5 wherein said flats are separated by diametrically disposed portions of said third surface, said third surface portions each having a conical configuration.
 12. The combination according to claim 1 wherein each of said first, said second and said third surfaces is disposed to prevent angular displacement of said roll neck relative to said coupling bore when said roll neck is fully inserted into said connector.
 13. The combination according to claim 1 wherein each of said first and said second surfaces are shaped for initially and continuOusly close-fitting engagement with complementary surfaces respectively of said roll neck as said roll neck is progressively inserted into said coupling bore.
 14. The conbination according to claim 1 wherein each of said first and said second surfaces is shaped to prevent angular displacement of said roll neck relative to said coupling as said roll neck is progressively inserted into said coupling bore. 